# -*- coding: utf-8 -*-
S = input()

if 'RRR' in S:
    print("3")
elif 'RR' in S:
    print("2")
elif 'R' in S:
    print("1")
else:
    print("0") S = input() S input() input if 'RRR' in S:
    print("3")
elif 'RR' in S:
    print("2")
elif 'R' in S:
    print("1")
else:
    print("0") 'RRR' in S 'RRR' S print("3") print "3" elif 'RR' in S:
    print("2") 'RR' in S 'RR' S print("2") print "2" elif 'R' in S:
    print("1") 'R' in S 'R' S print("1") print "1" print("0") print "0" S = input() input() S
# -*- coding: utf-8 -*-
S = input()

if 'RRR' in S:
    print("3")
elif 'RR' in S:
    print("2")
elif 'R' in S:
    print("1")
else:
    print("0")